The English word "abyss" directly derives from the Greek word used in this verse. It is the same word that the demons possessing the Gerasene demoniac used in entreating Jesus not to send them there (Luke 8:31). The Hebrew concept being expressed by the word is that of the lowest depth of a bottomless abode of the dead located under the earth, which is apparently a place of captivity for the most evil spiritual beings that pose the greatest danger to humans (as in the passage from Revelation cited in the question), or of those undergoing the maximum possible degree of separation from God. It is similar in meaning and function to the Greek word "tartarus" used by Peter in 2 Peter 2:4, which is usually translated as "hell".

Literally "the bottomless pit" is "the shaft /pit/well of the abyss" in the Greek. Another commentator says the bottomless pit in the Greek should be rendered, "the pit of the abyss"; it's the orifice of the hell where Satan and his demons dwell.
The Abyss has been referred to as the dwelling place of the dead
(Romans 10:7 --CSB or, “Who will go down into the abyss?” that is, to bring Christ up from the dead.)
(Romans 10:7 --NLT
And don’t say, ‘Who will go down to the place of the dead?’ (to bring Christ back to life again).”)
10:7 abyss here refers to the place of the dead, the underworld), and it is referred to as the dwelling place of demons (Luke 8:31).

The word for “bottomless pit” in Greek “abussos,” is translated in English as "abyss." That same word is used in Genesis 1:2 in the Greek version of the Old Testament in connection with the creation of the earth, but there is translated “deep.” The words “deep,” “bottomless pit,” and “abyss” here refer to the same thing - the earth in its totally dark, disorganized form before God made order of it.
Jeremiah, in describing this earth during the 1,000 years, used the same terms as these in Genesis 1:2: “without form, and void,” “no light,” “no man,” and “black” (Jeremiah 4:23, 25, 28). So, the abandoned, dark earth with no people alive is called the bottomless pit, or abyss, during the 1,000 years, just as it was in the very beginning before Creation.
Also, Isaiah 24:22 speaks of Satan and his angels during the 1,000 years as “gathered in the pit” and “shut up in the prison.” The destruction of those who reject God and the removal of God's people from the earth will leave the earth desolate.
In Revelation 20, John describes an angel who binds Satan with a great chain and throws him in the abyss. The term abyss in Scripture can be the grave, death, destruction, and the prison of the demons (Rom 10:7, Luke 8:31).